Embodiments of the inventive subject matter generally relate to the field of wireless communication systems and, more particularly, to a power save communication mechanism for wireless communication systems.
Unscheduled automatic power save delivery (U-APSD) can be implemented on a wireless local area network (WLAN) device to ensure quality of service (QoS) by prioritizing traffic (e.g., voice, video, etc.) exchanged between the WLAN device and an access point. In U-APSD, a data frame transmitted from the WLAN device to the access point (an uplink data frame) is used to trigger the access point. When the access point receives the uplink data frame, the access point starts an unscheduled service period and transmits buffered downlink data frames (if available) to the WLAN device. At the end of the service period, the access point transmits an end of service period (EOSP) notification to indicate that the access point has no buffered downlink data to transmit.